<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
    <head>
        <title>Showcase: Complex Flexbox Layout with Nested Containers</title>
        <link rel="author" title="Azul Layout" href="https://azul.rs/" />
        <meta name="flags" content="" />
        <meta name="assert" content="Flexbox should handle complex nested layouts with different flex-direction, justify-content, and align-items combinations." />
        <style type="text/css">
            * { margin: 0; padding: 0; }
            body {
                width: 800px;
                height: 600px;
                background: #f0f0f0;
            }
            .container {
                display: flex;
                width: 100%;
                height: 100%;
                flex-direction: column;
                padding: 20px;
            }
            .header {
                display: flex;
                height: 80px;
                background: #667eea;
                justify-content: space-between;
                align-items: center;
                padding: 0 20px;
                margin-bottom: 10px;
            }
            .header-left, .header-right {
                display: flex;
            }
            .header-item {
                width: 40px;
                height: 40px;
                background: #9ca3e8;
                margin-left: 10px;
            }
            .content {
                display: flex;
                flex: 1;
            }
            .sidebar {
                display: flex;
                flex-direction: column;
                width: 200px;
                background: #3b82f6;
                padding: 15px;
                margin-right: 10px;
            }
            .sidebar-item {
                height: 50px;
                background: #60a5fa;
                margin-bottom: 10px;
            }
            .main {
                display: flex;
                flex: 1;
                flex-direction: column;
            }
            .cards {
                display: flex;
                flex-wrap: wrap;
                flex: 1;
            }
            .card {
                display: flex;
                flex-direction: column;
                width: calc(33.333% - 10px);
                background: white;
                padding: 20px;
                justify-content: space-between;
                margin-right: 15px;
                margin-bottom: 15px;
            }
            .card-header {
                height: 40px;
                background: #10b981;
                margin-bottom: 10px;
            }
            .card-content {
                flex: 1;
                background: #f3f4f6;
            }
            .card-footer {
                height: 30px;
                background: #6366f1;
                margin-top: 10px;
            }
            .footer {
                display: flex;
                height: 60px;
                background: #1f2937;
                justify-content: center;
                align-items: center;
                margin-top: 10px;
            }
            .footer-item {
                width: 80px;
                height: 30px;
                background: #374151;
                margin-left: 20px;
            }
        </style>
    </head>
    <body>
        <div class="container">
            <div class="header">
                <div class="header-left">
                    <div class="header-item"></div>
                    <div class="header-item"></div>
                    <div class="header-item"></div>
                </div>
                <div class="header-right">
                    <div class="header-item"></div>
                    <div class="header-item"></div>
                </div>
            </div>
            <div class="content">
                <div class="sidebar">
                    <div class="sidebar-item"></div>
                    <div class="sidebar-item"></div>
                    <div class="sidebar-item"></div>
                    <div class="sidebar-item"></div>
                </div>
                <div class="main">
                    <div class="cards">
                        <div class="card">
                            <div class="card-header"></div>
                            <div class="card-content"></div>
                            <div class="card-footer"></div>
                        </div>
                        <div class="card">
                            <div class="card-header"></div>
                            <div class="card-content"></div>
                            <div class="card-footer"></div>
                        </div>
                        <div class="card">
                            <div class="card-header"></div>
                            <div class="card-content"></div>
                            <div class="card-footer"></div>
                        </div>
                        <div class="card">
                            <div class="card-header"></div>
                            <div class="card-content"></div>
                            <div class="card-footer"></div>
                        </div>
                        <div class="card">
                            <div class="card-header"></div>
                            <div class="card-content"></div>
                            <div class="card-footer"></div>
                        </div>
                        <div class="card">
                            <div class="card-header"></div>
                            <div class="card-content"></div>
                            <div class="card-footer"></div>
                        </div>
                    </div>
                </div>
            </div>
            <div class="footer">
                <div class="footer-item"></div>
                <div class="footer-item"></div>
                <div class="footer-item"></div>
                <div class="footer-item"></div>
            </div>
        </div>
    </body>
</html>
